Plasma display panels (referred to as “PDP” hereinafter) have become prevalent due to their advantages such as the relative ease to provide large-scale screens. Among the PDPs, alternative current (AC) types have become the mainstream due to the reliability and the picture quality characteristics.
PDPs of AC types have a structure wherein a pair of panel members (referred to as panel hereinafter) is placed opposite from each other while each other sandwiching discharge space. A front panel member (referred to as front panel hereinafter) out of the pair of panel members includes a plurality of pairs of scan electrode and sustain electrode, which are display electrode pairs, on the surface of a front substrate, and includes a dielectric layer and a dielectric protective layer that cover the display electrode pairs.
A back panel member (referred to as back panel hereinafter), which is the other panel out of the pair of panels, includes (i) a plurality of address electrodes in a striped pattern that are formed on the main surface of a back substrate, (ii) the dielectric layer that covers the address electrodes, (iii) protruding barrier ribs that are arranged between the address electrodes on the surface of the dielectric layer, and (iv) phosphor layers that are formed between the barrier ribs. It should be noted that the barrier ribs may be applied, arranged in parallel crosses in the back panel to ensure the prevention of crosstalk.
The front panel and the back panel are arranged such that the dielectric protective layer and the phosphor layers face each other, and scan electrodes and sustain electrodes intersect with address electrodes three dimensionally. The front panel and the back panel are sealed at the outer periphery. The discharge space that is divided by the barrier ribs between the front panel and the back panel, is filled with discharge gases such as Xenon (Xe)-Neon (Ne) based gas, or Xenon (Xe)-Neon (Ne)-Helium (He) based gas.
To drive the PDPs that have the above-described structure, it is generally known to apply the method in which three periods, a reset period, an address period, and a sustain discharge period, are repeated sequentially. Among the three periods, it is the sustain discharge period that relates to a picture display. During this period, a pulse voltage is impressed upon the scan electrodes and the sustain electrodes in selected display cells to generate surface discharge on the dielectric protective layer.
Meanwhile, PDPs have two major tasks to accomplish, which are to achieve low cost and low power consumption. To lower the power consumption, PDPs still have need of improvement, and it is essential to improve the luminous efficiency. To accomplish the task, it is considered to be effective to adopt a structure in which a discharge gap in the display cell is set to be large so that an electrical discharge path can be lengthened. However, in the conventional types of PDPs, a discharge between the scan electrode and the sustain electrode during the sustain discharge period is the surface discharge; therefore, a large amount of voltage needs to be impressed compared to opposite discharge. As a result, increasing the discharge gap creates a problem of increasing firing voltage.
In respect of restraining the increase of the firing voltage while sustaining the large discharge gap, it is preferable to apply a structure in which opposite discharge can be generated during the sustain discharge period. To achieve the above-described requirement, a structure of providing the discharge space between the scan electrode and the sustain electrode is under study. Suggested techniques include (i) a technique wherein the scan electrode and the sustain electrode are formed to span from the top to the sides of the barrier ribs which are located in the front panel (See Patent document 1), and (ii) a technique to form the scan electrode and the sustain electrode in a way that both of the electrodes are elevated very thickly.    [Patent Document 1] Japanese Patent Application Publication No. 2003-132804; and    [Patent Document 2] Japanese Patent Application Publication No. 2003-151449.